Consider using the CMB2 API.
<SITE_URL>/wp-json/cmb2/v1/boxes/<METABOX_ID>/fields/PhotoGalleryGroup?object_id=<POST_ID>&object_type=post
You will need to enable the API feature for your box/fields. Documentation for that is in the wiki.
Consider using the CMB2 API.
<SITE_URL>/wp-json/cmb2/v1/boxes/<METABOX_ID>/fields/PhotoGalleryGroup?object_id=<POST_ID>&object_type=post
You will need to enable the API feature for your box/fields. Documentation for that is in the wiki.